Slack adjuster



3 mentor I GMM nog Aug.-1o ,1926.

W. H. SAUVAGE SLACK ADJUSTER Filed May 17, 1924 Cil Patented Aug. 10, 1926.

UNTE- STATES WILLIAM I-I. SAUVAGE, OF NEW THE GO'ULD COUPLER Yoan, N. Y., AssreNon, BY MnsNn ASSIGNMENTS, To COMPANY, A conroRA'rIoN or MARYLAND.

SLACK ADJUSTER.

Application led'May 17, 1924. Serial No. 714,171.

ver is a combined dead and live lever, whereby as the power is applied to the live lever all three levers are moved to bring the brake vshoes into engagement with the respective 15y pairs of wheels.V

@ne of the Vobjects of the present invention is to providc'a simple and practical slack adjuster of the above general type which may be inexpensively manufactured and assembled and applied to bra-1re rigging and trucks now in use without n'laterial alteration.

A further object is to providemechanism of the above character which will be reliable and eriieient to taire up Yall of theVeXce'ss travel of the bralrerigging connected with the truck atreachcoinplete application and release of the'bralres.

@ther objects will be invpart obvious from the annexed drawing and in part indicated in connection therewith by the following analysis of the invention.

This invention accordingly consists in the features of construction, combination of parts and in the unique relation of the members and in the relative proportioning and disposition thereof, all as more completely outlined herein. f

To enable others skilled in the :art so fully to comprehend the underlying features in ord r that they may embody the same by numerous modifications in structure Aand relation contemplated-by this invention, a drawing depicting a preferred form has been annexed aspart of this disclosure..

Figure 1 is a side elevational view of such part-s of the brake rigging and slack adjuster mechanism as lsnecessary to understand the invention. v

Figure 2 is a detail view.

vReferring now in detail to Figure 1, 1 indicates a live'leveriand 2 what will be termed the dead lever, although. it is to be understood that this lever acts as a live lever for sniplyingv the brakes to the next adjacent schot wheels. The upper end ot the live movement lin the opposite direction as lever is connected by means of a pull rod 3 to any suitable source of power while ya connecting rod 4 is attached to the upper end of the dead lever The lower ends of these levers 1. and are connected by a telescoping push rod comprising an internal member 5 and a tubular terminating in an enlarged housing 7 provided with a plurality of permanent take up and holding means which, in the present casa is preferably composed of a plurality of holding dogs 8 adapted to grip therrod 5 when held iu canted position by means'othe helicalr spring v10. Immediately above the tie rod 6 is an adjusting rod 11 which extends between a pivot point 12' on the dead lever and a swivel. yol e13 on the live lever, shown in detail in Figure 2. Upon this rod 11 is a temporary take-up and holding mechanism which preferably includes a housing" 14., slidably mounted on said rod, having a dog a coiled spring 16 whereby it has a biting' ei agement with therod ll'to'prevent movement tl'iereofin one direction but allows rfree will be more fully hereinafter explained. Interposed between the housing 1d and the swiveled support 13 is a compression spring 17. T he live lever is provided with ay fulcrum point 1S at which point is usually connected the brake. shoe heads for carrying the shoes adapt-ed to engage the periphery of theadjacent wheel. The same istrue of the pivot point Q() on the dead lever 2. i

interposed between the point 18 and the central part of the adjusting rod 11 is an actuating rod 21. one end of which is bent downwardly and. around the rod 11 and spaced from the housing ed to ensure bralre shoe clearance at all times on release of the bra-kes. l/Tihen the brakes are applied thc-,upper end of the live lever 1 moves toward the left and carries the loop formed in rod 21 into engagement with the housing 14:. 1f excess travel takes place, due to wear of the parts, then this housing 14 is moved relatively towards the left to co1n-' press the spring 17 an exact amount equalto the excess travel.y v On release ofthe parts the live and dead leve-rs are restored to normal position, by the usual return spring and the bent over end 21 drops away from the hous-` ing 14 and allows the helical spring 17 yto expand, butthe dog F15-new has a biting en- 15 held in canted position by means ofv 14 a distance adaptmember 6, the latter f ceV gagement with this rod and it reacts against the swiveled connection to force he same relatively towards the left and carry the rod 5 out of its tubular casing 6 past the dogs 8, thus changing the effective length of this push rod 6 between the lower ends of the live :ind dead levers an amount corresponding` to the excess travel.

From the above it will be seen that the slack adjuster mechanism herein described operates to take up all of the excess travel temporarily on each application of the brakes and to permanently take up this excess travel on release of the brakes.

`When it is necessary to restore the parts to normal position for the purpose of replacing` worn brake shoes, then both-sets of dogs or holding devices 8 and l5 are moved to a position normal to the axis of the rods with which they co-act, thus permitting the rod 5 to telescope inwardly with respect to the part 6 and the housing' la to slide along' the .rod ll.

The mechanism which is simple and practical in construction, reliable and efficient in use and operation, is well adapted to accomplish all of the objects herein set forth.

llllithout further analysis, the foregoing` will so fully reveal the gist of this invention that others can, by applying` current knowledge, readily adapt it for various applications without omitting' certain features that, from the standpoint of the prior art, fairly constitute essential characteristics of the generic or specilic aspects of lthis invention, and, therefore, such adaptations should and are intended to be comprehended within the nuaaning,r and range of equivalency of the following claims.

llVhat I claim is l. In an automatic slack adjuster mechanism1 in combination, live and dead levers, a telescopic push rod connecting the lower ends of said levers, permanent take up and iolding means associated therewith for holdinfr the parts in adjusted position, an adjustable mechanism interposed between the live and dead levers includingr a temporary take up and holding mechanism, a spring); adapted to be compressed on excess travel during' application of the brakes, and to expand on release of the brakes to change the effective length of said push rod and permanently take up and hold the excess travel.

2. ln an automatic slack adjuster mechanism, in combination live and dead levers, a telescopic push rod connecting: the lower ends of said levers, permanent take up and holding mechanism associated therewith for vholding the parts in adjusted position, adjusting mechanism connecting intermediate parts of said levers, including?,` a rod extending,` from the live lever to the dead lever and pivotally connected with it, `and a second rod extending from the live lever to a portion of 'Il aime.

said iirst mentioned rod, temporary take up and holding means mounted upon said first mentioned rod adapted to be actuated by the second mentioned rod on excess travel, and a spring associated with the first mentioned rod adapted to be compressed on excess travel on application of the brakes, and to expand to actuate the permanent take up and holding mechanism when the brakes are released.

3. In an automatic slack adjuster mechanism, in combination, a telescopic pushrod connecting; the ends of said levers, including,` a permanent take up and holding mechanism, a second rod parallel thereto connectingr the intermediate parts of said levers and having a temporary take up mechanism thereon, a spring associated with said temporary take up mechanism, when the same is actuated, means adapted to connect the live lever with said temporary take up mechanism when excess travel occurs, to move the same along said rod to compress said spring', said springrei-acting upon said live lever to cause a relative movement thereof when the brakes are released and a relative adjustment of the telescopic push rod connecting the lower ends of said levers. v

4. in an automatic slack adjuster mecha.- nism. in combination, a live lever, a combined live and dead lever, a push rod connectino; the said levers,y an adjusting rod parallel thereto connecting the intermediate parts of said levers and a third rod substantially parallel to the i'irst interposed between the live lever and an intermediate part of said second rod, a spring adapted to be compressed on excess travel of the brakes during' the application thereof, said spring being adapted to expand on release of the brakes, and to cause an adjustment in the first mentioned rod.

5. In an automatic slack adjuster mechanism, in combination` a live leve-r, a combined live and dead lever, a push rod connecting the said levers, an adjusting rod parallel thereto connecting the intermediate parts of said levers and a third rod substantially parallel to the i'irst interposed hetween the live leverv and an intermediate part of said second rod, a springadapted to he compressed on excess travel of the brakes during the application thereof, said spring' being` adapted to expand on release of the brakes, and to-cause an adjustment in the first mentioned rod, said .first mentioned rod havingV a solid part and a tubular part and a plurality of holding. dogs carried by the tubular part adapted to engage the solid part and to prevent relative movement thereof during the application of the brakes.

In witness whereof *lf have signed my WiLLixM in. sanvaan; j 

